Progress 04/13/02 to 06/27/06
Outputs
Progress Report 1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter? The overall goal of this project is to study the basic physical processes that govern wind erosion and dust emissions in agricultural regions at multiple scales, to provide a basis for the development of mitigation strategies. The specific objectives of this project are to: 1. relate sand transport (saltation) and atmospheric turbulence, as affected by soil surface conditions, with dust emissions at the sub-field and field- scale. 2. define plant and soil surface properties that impact wind erosion processes at the field-scale. 3. use long-term dust records and geographic information systems to relate ambient dust levels and potential wind erosion to changing land-use practices at a regional-scale and define linkages between climatic conditions and regional dust levels. Wind erosion
causes about 44 percent of the 2.13 billion tons per year of soil loss from U.S. cropland. In the Great Plains alone, about 5 million acres are moderately to severely damaged by wind erosion each year. Sustainable agriculture is possible only if we conserve soil resources for future generations. Reducing wind erosion helps conserve topsoil and reduces air and water pollution from airborne sediments. Reducing wind erosion can impact agricultural production by reducing production costs. Deposition of transported dust on crops decreases their yield, reduces their economic value, and hinders their processing. Considerable crop losses occur each year from "sandblasting" of seedlings caused by abrasive damage to plant tissues. The need for a solid scientific approach to the wind erosion problem increases as the world population grows and the need to utilize our resources to the fullest becomes more critical. In addition, objective information regarding the wind erosion process will
improve the scientific basis for making decisions on farm policies and environmental issues. This CRIS project is aligned with National Programs 203 and 202. This CRIS contributes to two components of the ARS NP 203 National Air Quality Program and four components of the Soil Resources Management Programs. Objectives 1 and 3 of this CRIS contribute to the Particulate Emissions from Wind Erosion objective of the Particulate Emissions Component of the Air Quality National Program by developing the science basis for particle emission and control strategies needed for policy and regulatory decisions. This CRIS is also closely tied to the Agricultural Operations objective of the Particulate Emissions Component of the Air Quality National Program by providing information on soil surface conditions impacting particle emissions. Objectives 2 and 3 of this CRIS are closely tied to the Erosion: Wind, Rainfall, Irrigation and Tillage Problems objective of the Soil Conservation and Restoration
component of the ARS NP 202 Soil Resource Management National Program by providing knowledge on plant and surface properties that cause wind erosion that reduces productivity and identifying management practices that cause soil degradation. This CRIS also relates to the Infiltration and Retention and Soil Water Availability objectives of the Soil Water component of the Soil Resource Management Program by providing information on soil properties that impact infiltration as well as wind erosion; the Interactions Between Soil Management and Soil Biota objective of the Soil Biology component of the Soil Resource Management Program by providing information on soil microbiological factors that impact soil properties related to sustainable management; and the Developing Sustainable Soil Management Systems objective of the Sustainable Soil Management Systems component of the Soil Resource Management Program by identifying land use practices that reduce erosion and produce sustainable land
management systems. 2. List by year the currently approved milestones (indicators of research progress) Year 1 (FY2002/2003) Obj. 1. Install/implement field dust study. Collect data and evaluate for contingencies. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit. Collect data. Analyze data. Work with WERU on aggregate stability data. Obj. 3. Obtain past TSP, PM10 data from TNRCC. Obtain soils and satellite imagery and develop software for GIS model. Locate soil surface field test sites. TSP measurements. Obtain climate data from NOAA. Complete first year of meteorological and TSP measurements at sampling sites. Collect samples, begin analyses of particle characteristics. Present data at meetings and publish preliminary findings. Year 2. (FY2003/2004) Obj. 1. Install/implement experimental design. Collect data. Present data at meetings and publish preliminary findings. Obj. 2. Plant and instrument experimental plots as rainfall and planting
windows permit. Collect data. Analyze data. Develop aggregate stability field tests as needed. Obj. 3. Complete second year of meteorological and TSP measurements at sampling sites. Present data at meetings and publish roughness findings on TSP measurements. Continue particle characteristics analyses. Make tests of aggregation using citrus oil and begin data analyses. Hypothesis 3 abandoned due to lack of collaborator support. Year 3. (FY2004/2005) Obj. 1. Continue data analysis and publish results. Install/implement experimental design if insufficient data from first two years. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit. Continue aggregate stability field tests. Collect data. Analyze data. Obj. 3. Complete third year of meteorological and TSP measurements at sampling sites. Present data at meetings and publish preliminary findings. Finish particle characteristics analyses and continue data analyses. Present data at meetings and publish
preliminary findings. Year 4 (FY2005/2006) Obj. 1. Continue data analysis and publish results if sufficient data was not collected in first two years. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit if insufficient data in first three years. Analyze data and publish results. Obj. 3. Complete fourth year of meteorological and TSP measurements at sampling sites. Finish data analyses and publish results. Finish particle character analyses and continue data analyses. Year 5. (FY2006/2007) Obj. 1. No milestone recognized Obj. 2. Analyze data and publish results if fourth year of field investigations are necessary. Obj. 3. Complete fifth year of TSP measurements at sampling sites. Publish results. Complete fifth year of meteorological and TSP measurements at sampling sites. 4a List the single most significant research accomplishment during FY 2006. Observing Soil Properties from Afar: Computer models are available to predict wind erosion for
locations of a variety of sizes, from fields to regional-sized areas. Methods to assess changes in soil surface properties are needed in order to improve and create better models. Remote sensing, observing surface properties from a distance, may provide a way to detect changes in soil surface properties affecting wind erosion without disturbing the surface and to do so for a wide variety of area sizes. In this study, we used a device that measures the reflectance of light wavelengths from the soil to compare three soils that were modified by applying artificial rainfall and then abrading the soils with sand in a wind tunnel. With the measurements of reflectance from the soil surface we were successful in identifying differences in soil texture (the relative amount of sand, silt and clay particles in the soil), the occurrence of a soil crust created by the artificial rainfall, and the presence of loose sand on the crust surface that could easily blow away. These results demonstrated
that this type of remote sensing of the soil surface can be used to distinguish differences in soil surfaces caused by rainfall and wind erosion, without disturbing the soil surface. Since similar light reflectance measurement devices are carried on several of the earth-observing satellites currently in orbit, this research has potential for use in improving our understanding of soil properties and ultimately identifying and measuring erosion on a global scale. If this method can be successfully extended to earth-observing platforms, significant improvements of erosion, hydrological and other earth processes models will result. This research is related to the Particulate Emissions from Wind Erosion Component of NP203 (National Air Quality Program) and is closely tied to the Erosion: Wind, Rainfall, Irrigation and Tillage Problems objective of NP202 (Soil Resources Management National Program). 5. Describe the major accomplishments to date and their predicted or actual impact. 1.
Developed new unattended sequential dust sampling system to measure dust remotely for weekly periods. This system will provide higher quality atmospheric dust data than now possible with currently available commercial instruments. This research is related to the Particulate Emissions Component of NP203 and Component 1, Soil Conservation and Restoration of NP202. 2. A new method was developed that allows for the rapid determination of the wind speed that dust will begin moving under natural wind conditions, during periods of active sand movement in the field using commercially available equipment. This new method allows for routine monitoring of surface threshold conditions in the field and will be important in the validation of dust emission models that predict effects of wind erosion on air quality and provides an important method to remotely detect when wind erosion occurs in the field and evaluate the relative erodibility of the site under study. This research is related to the
Particulate Emissions Component of NP203 and Component 1, Soil Conservation and Restoration of NP202. 3. Validation of wind erosion models using field data is needed to understand how reliably and accurately they predict wind erosion. We used up to 41 measured wind erosion events to evaluate several wind erosion models currently in use. Although the results were variable, in general, the three erosion models tested (WEQ, WESS, RWEQ) tended to predict less erosion than that observed. These studies could have a significant impact on erosion policy when based on model estimates, since they show that estimates of erosion using models will generally be conservative. This research is related to the Particulate Emissions Component of NP203 and Component V, Productive and Sustainable Soil Management Systems of NP202. 4. We have demonstrated that less than 5 percent of several important nutrients deposited in an area downwind of eroding farm fields may be attributed to the fugitive dust
itself. The vast majority of these chemical species, even in a region noted as a locally important source of fugitive dust, is from anthropogenic sources. As agriculture comes under increasing scrutiny for impairing air quality through tillage and harvesting operation, this information may be used to develop and/or modify official policy and regulations that affect the producers' operations and profit margin. This research is related to the Particulate Emissions Component of NP203 and Component V, Productive and Sustainable Soil Management Systems of NP202. 5. Measurements of climatic variables and airborne sediment mass and concentration were made during three strong wind events on a bare, fine sandy loam field in west Texas. This study clearly shows that dust flux estimate were very sensitive to dust concentration measurement height and sampler location in relation to dust source. During the most intense storm event, the PM10 flux between heights of 2m to 5m measured at the
tower 200m from the unerodible boundary was almost 2.5 times as that measured at the tower 100m from the unerodible boundary. Results of this study show the critical importance of selected sampling variables when identifying fugitive dust strengths and sources. This research is related to the Particulate Emissions Component of NP203 and Component 1, Soil Conservation and Restoration of NP202. 6. In semi-arid agricultural regions that lack significant industrial sources of particulate matter, elevated levels of particulate matter generally indicate blowing dust associated with regional-scale wind erosion activity. Thus, long-term records of blowing dust can provide valuable information regarding changing regional wind erosion activity in some regions. We have collected a continuous record of daily dust samples in the Lubbock area over a period of 8.5 years. These results show that current ambient dust levels are significantly lower than those measured by other local, state and
federal agencies in the past. The adoption of improved agricultural practices has played a crucial role in reducing wind erosion activity and dust emissions on the Southern High Plains. This research is related to the Particulate Emissions Component of NP203 and Component V, Productive and Sustainable Soil Management Systems of NP202. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Wind tunnel design technology was transferred to a scientist in Iceland.
Impacts
(N/A)
Publications
- Buschiazzo, D.E., Zobeck, T.M. 2006. Wind Erosion Prediction using WEQ, RWEQ and WEPS in an TNTIC Haplustoll of the Argentinean Pampas [abstract]. International Conference on Aeolian Research, July 24-28, 2006, Guelph, Ontario, Canada. p. 191.
- Gill, T., Zobeck, T.M., Stout, J.E. 2006. Technologies for laboratory generation of dust from geological materials. Journal of Hazardous Materials. 132:23-38.
- Zobeck, T.M., Van Pelt, R.S. 2004. Erosion: Wind-induced. In: Hillel, D., editor. Encyclopedia of Soils in the Environment. Oxford, UK;Elsevier, Ltd. p. 470-478.
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Progress 10/01/04 to 09/30/05
Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? The overall goal of this project is to study the basic physical processes that govern wind erosion and dust emissions in agricultural regions at multiple scales, to provide a basis for the development of mitigation strategies. The specific objectives of this project are to: 1) relate sand transport (saltation) and atmospheric turbulence, as affected by soil surface conditions, with dust emissions at the sub-field and field- scale, 2) define plant and soil surface properties that impact wind erosion processes at the field-scale, and 3) use long-term dust records and geographic information systems to relate ambient dust levels and potential wind erosion to changing land-use practices at a regional-scale and define linkages between climatic conditions and regional dust levels. Wind erosion causes about
44% of the 2.13 billion tons per year of soil loss from U.S. cropland. In the Great Plains alone, about 5 million acres are moderately to severely damaged by wind erosion each year. Sustainable agriculture is possible only if we conserve soil resources for future generations. Reducing wind erosion helps conserve topsoil and reduces air and water pollution from airborne sediments. Reducing wind erosion can impact agricultural production by reducing production costs. Deposition of transported dust on crops decreases their yield, reduces their economic value, and hinders their processing. Considerable crop losses occur each year from "sandblasting" of seedlings caused by abrasive damage to plant tissues. The need for a solid scientific approach to the wind erosion problem increases as the world population grows and the need to utilize our resources to the fullest becomes more critical. In addition, objective information regarding the wind erosion process will improve the scientific
basis for making decisions on farm policies and environmental issues. This project contributes to two components of the ARS NP 203 National Air Quality Program and four components of the Soil Resources Management Programs. Objectives 1 and 3 of this CRIS contribute to the Particulate Emissions from Wind Erosion objective of the Particulate Emissions Component of the Air Quality National Program by developing the science basis for particle emission and control strategies needed for policy and regulatory decisions. This CRIS is also closely tied to the Agricultural Operations objective of the Particulate Emissions Component of the Air Quality National Program by providing information on soil surface conditions impacting particle emissions. Objectives 2 and 3 of this CRIS are closely tied to the Erosion: Wind, Rainfall, Irrigation and Tillage Problems objective of the Soil Conservation and Restoration component of the ARS NP 202 Soil Resource Management National Program by providing
knowledge on plant and surface properties that cause wind erosion that reduces productivity and identifying management practices that cause soil degradation. This CRIS also relates to the Infiltration and Retention and Soil Water Availability objectives of the Soil Water component of the Soil Resource Management Program by providing information on soil properties that impact infiltration as well as wind erosion; the Interactions Between Soil Management and Soil Biota objective of the Soil Biology component of the Soil Resource Management Program by providing information on soil microbiological factors that impact soil properties related to sustainable management; and the Developing Sustainable Soil Management Systems objective of the Sustainable Soil Management Systems component of the Soil Resource Management Program by identifying land use practices that reduce erosion and produce sustainable land management systems. 2. List the milestones (indicators of progress) from your Project
Plan. Year 1 (FY2002/2003) Obj. 1. Install/implement field dust study. Collect data and evaluate for contingencies. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit. Collect data. Analyze data. Work with WERU on aggregate stability data. Obj. 3. Obtain past TSP, PM10 data from TNRCC. Obtain soils and satellite imagery and develop software for GIS model. Locate soil surface field test sites. TSP measurements. Obtain climate data from NOAA. Complete first year of meteorological and TSP measurements at sampling sites. Collect samples, begin analyses of particle characteristics. Present data at meetings and publish preliminary findings. Year 2. (FY2003/2004) Obj. 1. Install/implement experimental design. Collect data. Present data at meetings and publish preliminary findings. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit. Collect data. Analyze data. Develop aggregate stability field tests as needed.
Obj. 3. Complete second year of meteorological and TSP measurements at sampling sites. Present data at meetings and publish roughness findings on TSP measurements. Continue particle characteristics analyses. Make tests of aggregation using citrus oil and begin data analyses. Hypothesis 3 abandoned due to lack of collaborator support. Year 3. (FY2004/2005) Obj. 1. Continue data analysis and publish results. Install/implement experimental design if insufficient data from first two years. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit. Continue aggregate stability field tests. Collect data. Analyze data. Obj. 3. Complete third year of meteorological and TSP measurements at sampling sites. Present data at meetings and publish preliminary findings. Finish particle characteristics analyses and continue data analyses. Present data at meetings and publish preliminary findings. Year 4 (FY2005/2006) Obj. 1. Continue data analysis and publish
results if sufficient data was not collected in first two years. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit if insufficient data in first three years. Analyze data and publish results. Obj. 3. Complete fourth year of meteorological and TSP measurements at sampling sites. Finish data analyses and publish results. Finish particle character analyses and continue data analyses. Year 5. (FY2006/2007) Obj. 2. Analyze data and publish results if fourth year of field investigations are necessary. Obj. 3. Complete fifth year of TSP measurements at sampling sites. Publish results. Complete fifth year of meteorological and TSP measurements at sampling sites. 3a List the milestones that were scheduled to be addressed in FY 2005. For each milestone, indicate the status: fully met, substantially met, or not met. If not met, why. 1. Continue data analysis and publish results if sufficient data was not collected in first two years. Milestone
Substantially Met 2. Plant and instrument experimental plots as rainfall and planting windows permit if insufficient data in first three years. Analyze data and publish results. Milestone Fully Met 3. Complete fourth year of meteorological and TSP measurements at sampling sites. Finish data analyses and publish results. Finish particle character analyses and continue data analyses. Milestone Fully Met 3b List the milestones that you expect to address over the next 3 years (FY 2006, 2007, and 2008). What do you expect to accomplish, year by year, over the next 3 years under each milestone? Year 5. (FY2006/2007) Obj. 2. Analyze data and publish results if fourth year of field investigations are necessary. We will analyze data and publish results. Obj. 3. Complete fifth year of TSP measurements at sampling sites. Publish results. This was published in 2003. Complete fifth year of meteorological and TSP measurements at sampling sites. Publish results of all wind profile data including
Owens effect study begun 2 years ago. In addition, we will continue on-going measurements of meteorological and TSP measurements at sampling sites. FY2007/2008 - This project will be combined with 6208-12000-008 and be evaluated under NP202 in December 2005. 4a What was the single most significant accomplishment this past year? New Technique to Determine Threshold of Blowing Soil: A basic feature of any wind-eroding surface is its threshold - the wind speed at which sediment transport is initiated. Threshold is an important parameter in wind erosion research and in the field of aeolian research in general. Threshold is essentially a function of soil surface conditions; when comparing surfaces, the higher value of threshold indicates a surface that is less erodible. Scientists with the Cropping Systems Research Laboratory, Lubbock, Texas, have developed a new technique that provides a means of determining threshold with a sampling system that continuously collects wind data, along
with critical information regarding saltation activity. Further measurements of the threshold velocity at a number of sites in and around the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico for a period of three months suggest that this new method for determining threshold, which had previously been developed and tested on a flat sandy surface, can be used in a complex rangeland setting. This technique provides an important method to remotely detect when wind erosion occurs in the field and evaluate the relative erodibility of the site under study. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. 1. Developed new unattended sequential dust sampling system to measure dust remotely for weekly periods. This system will provide higher quality atmospheric dust data than now possible with currently available commercial instruments. This research is related to the Particulate Emissions Component of NP203 and
Component 1, Soil Conservation and Restoration of NP202. 2. A new method was developed that allows for the rapid determination of the wind speed that dust will begin moving under natural wind conditions, during periods of active sand movement in the field using commercially available equipment. This new method allows for routine monitoring of surface threshold conditions in the field and will be important in the validation of dust emission models that predict effects of wind erosion on air quality and provides an important method to remotely detect when wind erosion occurs in the field and evaluate the relative erodibility of the site under study. This research is related to the Particulate Emissions Component of NP203 and Component 1, Soil Conservation and Restoration of NP202. 3. Validation of wind erosion models using field data is needed to understand how reliably and accurately they predict wind erosion. We used up to 41 measured wind erosion events to evaluate several wind
erosion models currently in use. Although the results were variable, in general, the three erosion models tested (WEQ, WESS, RWEQ) tended to predict less erosion than that observed. These studies could have a significant impact on erosion policy when based on model estimates, since they show that estimates of erosion using models will generally be conservative. This research is related to the Particulate Emissions Component of NP203 and Component V, Productive and Sustainable Soil Management Systems of NP202. 4. We have demonstrated that less than 5% of several important nutrients deposited in an area downwind of eroding farm fields may be attributed to the fugitive dust itself. The vast majority of these chemical species, even in a region noted as a locally important source of fugitive dust, is from anthropogenic sources. As agriculture comes under increasing scrutiny for impairing air quality through tillage and harvesting operation, this information may be used to develop and/or
modify official policy and regulations that affect the producers' operations and profit margin. This research is related to the Particulate Emissions Component of NP203 and Component V, Productive and Sustainable Soil Management Systems of NP202. 5. Measurements of climatic variables and airborne sediment mass and concentration were made during three strong wind events on a bare, fine sandy loam field in west Texas. This study clearly shows that dust flux estimates were very sensitive to dust concentration measurement height and sampler location in relation to dust source. During the most intense storm event, the PM10 flux between heights of 2m to 5m measured at the tower 200m from the unerodible boundary was almost 2.5 times as that measured at the tower 100m from the unerodible boundary. Results of this study show the critical importance of selected sampling variables when identifying fugitive dust strengths and sources. This research is related to the Particulate Emissions
Component of NP203 and Component 1, Soil Conservation and Restoration of NP202. 6. In semi-arid agricultural regions that lack significant industrial sources of particulate matter, elevated levels of particulate matter generally indicate blowing dust associated with regional-scale wind erosion activity. Thus, long-term records of blowing dust can provide valuable information regarding changing regional wind erosion activity in some regions. We have collected a continuous record of daily dust samples in the Lubbock area over a period of 8.5 years. These results show that current ambient dust levels are significantly lower than those measured by other local, state and federal agencies in the past. The adoption of improved agricultural practices has played a crucial role in reducing wind erosion activity and dust emissions on the Southern High Plains. This research is related to the Particulate Emissions Component of NP203 and Component V, Productive and Sustainable Soil Management
Systems of NP202. Accomplishments under this project contribute to the achievement of ARS Strategic Plan Goal 5, Objective 2, Performance Measure 3, in that project accomplishments contribute substantially to attainment of the Agency FY 2007 target of developing management strategies for reducing wind erosion and dust emission. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Dr. Van Pelt was invited in Dec. 2004 to present the results of his dust chemistry investigations to the Environmental Sciences Program at the University of Texas at El Paso. Drs. Van Pelt and Zobeck were invited to present the results of their dust investigations to the scientific community associated with the Waste Isolation Pilot Plant at the Carlsbad Environmental Monitoring and Research Center in February 2005.
Impacts
(N/A)
Publications
- Stout, J.E. 2004. A method for establishing the critical threshold for aeolian transport. Earth Surface Processes and Landforms. 29(10):1195-1207.
- Stout, J.E., Lee, J.A. 2003. Indirect evidence of wind erosion trends on the Southern High Plains of North America. Journal of Arid Environments. 55(1):43-61.
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Progress 10/01/03 to 09/30/04
Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? The overall goal of this project is to study the basic physical processes that govern wind erosion and dust emissions in agricultural regions at multiple scales, to provide a basis for the development of mitigation strategies. The specific objectives of this project are to: 1) relate sand transport (saltation) and atmospheric turbulence, as affected by soil surface conditions, with dust emissions at the sub-field and field- scale. 2) define plant and soil surface properties that impact wind erosion processes at the field-scale. 3) use long-term dust records and geographic information systems to relate ambient dust levels and potential wind erosion to changing land-use practices at a regional-scale and define linkages between climatic conditions and regional dust levels. Wind erosion causes about 44% of
the 2.13 billion tons per year of soil loss from U.S. cropland. In the Great Plains alone, about 5 million acres are moderately to severely damaged by wind erosion each year. Sustainable agriculture is possible only if we conserve soil resources for future generations. Reducing wind erosion helps conserve topsoil and reduces air and water pollution from airborne sediments. Reducing wind erosion can impact agricultural production by reducing production costs. Deposition of transported dust on crops decreases their yield, reduces their economic value, and hinders their processing. Considerable crop losses occur each year from sandblasting of seedlings, causing abrasive damage to plant tissues. The need for a solid scientific approach to the wind erosion problem increases as the world population grows and the need to utilize our resources to the fullest becomes more critical. In addition, objective information regarding the wind erosion process will improve the scientific basis for
making decisions on farm policies and environmental issues. This CRIS contributes to two components of the NP 203 National Air Quality Program and four components of the NP 202 Soil Resources Management Programs. Objectives 1 and 3 of this CRIS contribute to the Particulate Emissions from Wind Erosion objective of the Particulate Emissions Component of the Air Quality National Program, by developing the science basis for particle emission and control strategies needed for policy and regulatory decisions. This CRIS is also closely tied to the Agricultural Operations objective of the Particulate Emissions Component of the Air Quality National Program, by providing information on soil surface conditions impacting particle emissions. Objectives 2 and 3 of this CRIS are closely tied to the Erosion: Wind, Rainfall, Irrigation and Tillage Problems objective of the Soil Conservation and Restoration component of the ARS NP 202 Soil Resource Management National Program, by providing knowledge
on plant and surface properties that cause wind erosion that reduces productivity and identifying management practices that cause soil degradation. This CRIS also relates to the Infiltration and Retention and Soil Water Availability objectives of the Soil Water component of the Soil Resource Management Program, by providing information on soil properties that impact infiltration as well as wind erosion; the Interactions Between Soil Management and Soil Biota objective of the Soil Biology component of the Soil Resource Management Program, by providing information on soil microbiological factors that impact soil properties related to sustainable management; and the Developing Sustainable Soil Management Systems objective of the Sustainable Soil Management Systems component of the Soil Resource Management Program, by identifying land use practices that reduce erosion and produce sustainable land management systems. 2. List the milestones (indicators of progress) from your Project Plan.
Year 1 (FY2002/2003) Obj. 1. Install/implement field dust study. Collect data and evaluate for contingencies. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit. Collect data. Analyze data. Work with WERU on aggregate stability data. Obj. 3. Obtain past TSP, PM10 data from TNRCC. Obtain soils and satellite imagery and develop software for GIS model. Locate soil surface field test sites. TSP measurements. Obtain climate data from NOAA. Complete first year of meteorological and TSP measurements at sampling sites. Collect samples, begin analyses of particle characteristics. Present data at meetings, and publish preliminary findings. Year 2. (FY2003/2004) Obj. 1. Install/implement experimental design. Collect data. Present data at meetings and publish preliminary findings. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit. Collect data. Analyze data. Develop aggregate stability field tests as needed. Obj. 3.
Complete second year of meteorological and TSP measurements at sampling sites. Present data at meetings and publish roughness findings on TSP measurements. Continue particle characteristics analyses. Make tests of aggregation using citrus oil and begin data analyses. Hypothesis 3 abandoned due to lack of collaborator support. Year 3. (FY2004/2005) Obj. 1. Continue data analysis and publish results. Install/implement experimental design if insufficient data from first two years. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit. Continue aggregate stability field tests. Collect data. Analyze data. Obj. 3. Complete third year of meteorological and TSP measurements at sampling sites. Present data at meetings and publish preliminary findings. Finish particle characteristics analyses and continue data analyses. Present data at meetings and publish preliminary findings. Year 4 (FY2005/2006) Obj. 1. Continue data analysis and publish results if
sufficient data was not collected in first two years. Obj. 2. Plant and instrument experimental plots as rainfall and planting windows permit if insufficient data in first three years. Analyze data and publish results. Obj. 3. Complete fourth year of meteorological and TSP measurements at sampling sites. Finish data analyses and publish results. Year 5. (FY2006/2007) Obj. 2. Analyze data and publish results if fourth year of field investigations are necessary. Obj. 3. Complete fifth year of TSP measurements at sampling sites. Publish results. Complete fifth year of meteorological and TSP measurements at sampling sites. 3. Milestones: A. List the milestones that were scheduled to be addressed in FY 2004. How many milestones did you fully or substantially meet in FY 2004 and indicate which ones were not fully or substantially met, briefly explain why not, and your plans to do so. See milestones above under FY 2003/2004 and FY 2004/2005 Objective 1. Measured saltation and dust
generation on field site. Analyzed data and submitted paper for publication. The experimental design has been greatly enhanced and now consists of four towers with three dust samplers each and sonic anemometers at each sampling height on the center tower. Sensit impact sensors and creep samplers have been added to the design at the west, center, and east towers, and TEOMs have been added at the center and east towers. Near-surface wind profile data is also being collected at the center tower. The last field season had no significant wind erosion events, and therefore publication milestone relates to data collected in 2003. Objective 2. One year of data from this investigation has been collected, analyzed, and reported in conference proceedings (13th ISCO). Insufficient wind erosion events for the last two field seasons have placed us behind the projected time line for this investigation. Wind profile measurements have been collected, analyzed, and are in the preparation stages for
publication. Preliminary results will be presented at the International Symposium on Sand and Dust Storms in Beijing, China, this September. Worked with WERU, Manhattan scientist to analyze aggregate stability data for use in surface soil property model. Objective 3. The results of the chemical, physical, and enzyme activities of fugitive dust have been reported in two conference abstracts, one conference proceedings, and a peer-reviewed journal article is currently in review. B. List the milestones that you expect to address over the next 3 years (FY 2005, 2006, & 2007). What do you expect to accomplish, year by year, over the next 3 years under each milestone? FY2005 Objective 1. Continue data collection activities. Analyze data. Objective 2, Continue data collection activities. Analyze data. Hypothesis 2: Will release findings on relation of wind erosion roughness parameters and aerodynamic roughness. Objective 2, Hypothesis 3: Will release information on effect of soil
management, soil properties and climate on aggregate stability. Objective 3, Hypothesis 4: We will quantify chemical properties, enzyme activities and the levels and types of microorganisms, including pathogens, transported in dust. FY2006 Objective 1: Will describe refinements in a technique to determine threshold wind speed based on saltation activity and relate dust emission to saltation activity. Continue data collection activities. Analyze data. Report results. Objective 2. Continue data collection activities. Analyze data. Report results. Objective 3, Hypothesis 4: We will release information that quantifies chemical properties, enzyme activities, and the levels and types of microorganisms. FY 2007 Objective 1. Analyze data. Publish results. Objective 2. Analyze data. Publish results of all wind profile data including Owens effect study. 4. What were the most significant accomplishments this past year? A. Single Most Significant Accomplishment: Knowledge of the physical,
chemical, and microbiological characteristics of dust is critically needed to understand the effects of dust deposition on plants, animals and humans. This information greatly enhances our knowledge of dust-borne transport of these materials over population centers and into adjacent watersheds. Several dust samples, source soils, and soils under natural filters from the Big Spring area were analyzed for particle size distribution, plant nutrient contents, trace metal contents, selected radionuclide contents, and enzyme activities. We have demonstrated that less than 5% of several important nutrients deposited in an area downwind of eroding farm fields may be attributed to the fugitive dust itself. The vast majority of these chemical species, even in a region noted as a locally important source of fugitive dust, is from anthropogenic sources. As agriculture comes under increasing scrutiny for impairing air quality through tillage and harvesting operation, this information may be
used to develop and/or modify official policy and regulations that affect the producers' operations and profit margin. These results have been reported in two conference abstracts, one conference proceedings article, and in one peer-reviewed journal article that is currently in review. B. Other Significant Accomplishments: Since fugitive dust particulate matter emission limits have been established by the United States Environmental Protection Agency, information on dust generation and transport mechanics from agricultural fields is needed to develop mitigation strategies. Measurements of climatic variables and airborne sediment mass and concentration were made during three strong wind events on a bare, fine sandy loam field in west Texas. This study clearly shows that dust flux estimate were very sensitive to dust concentration measurement height and sampler location in relation to dust source. During the most intense storm event, the PM10 flux between heights of 2m to 5m measured
at the tower 200m from the unerodible boundary was almost 2.5 times as that measured at the tower 100m from the unerodible boundary. Results of this study show the critical importance of selected sampling variables when identifying fugitive dust strengths and sources. C. Significant Activities that support special target population: None 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. Developed new unattended sequential dust sampling system to measure dust remotely for weekly periods. This system will provide higher quality atmospheric dust data than now possible with currently available commercial instruments. A new method was developed that allows for the rapid determination of the wind speed at which dust will begin moving under natural wind conditions, during periods of active sand movement in the field using commercially available equipment. This new method allows for routine monitoring of surface threshold
conditions in the field and will be important in the validation of dust emission models that predict effects of wind erosion on air quality. Validation of wind erosion models using field data is needed to understand how reliably and accurately they predict wind erosion. We used up to 41 measured wind erosion events to evaluate several wind erosion models currently in use. Although the results were variable, in general, the three erosion models tested (WEQ, WESS, RWEQ) tended to predict less erosion than that observed. These studies could have a significant impact on erosion policy when based on model estimates, since they show that estimates of erosion using models will generally be conservative. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? A
new and potentially useful field instrument was developed in a cooperative effort between the USDA-Agricultural Research Service and Texas Tech University. The instrument is best described as a flat-plate wind erosion sensor that detects grains as they skip across the face of a piezoelectric sensor. The main constraint to the adoption of this technology is that most researchers in the field of wind erosion research lack the skills necessary to build such a complex electronic device. Hopefully, a private company can be found to manufacture and sell these instruments to a very limited market. We reformulated a previously derived equation that relates saltation activity and relative wind strength such that threshold may be calculated from measurements of saltation activity, wind speed, and turbulence intensity and field tests were performed to determine its usefulness on a sandy surface in West Texas. Technology has been transferred to another ARS dust researcher and to visiting
producers at a field day held in conjunction with TCEX in September 2003. Technology also has been shared with researchers attending several national and international conferences.
Impacts
(N/A)
Publications
- Ravi, S., D'Ordorico, P., Over, T.M., Zobeck, T.M. 2004. On the effect of air humidity on soil susceptibility to wind erosion: the case of air-dry soils. Geophysical Research Letters. 31:LO9501.
- Van Pelt, R.S., Zobeck, T.M. 2004. Effects of polyacrylamide, cover crops, and crop residue management on wind erosion. Proceedings 13th International Soil Conservation Organization Conference, July 2-9, 2004, Brisbane, Australia. 4 p.
- Van Pelt, R.S., Zobeck, T.M., Acosta Martinez, V., Chavez, J.A., Ketterer, M.E., Gill, T.E., Baker, J.T. 2003. Transport of nutrients, soil carbon, trace metals, and enzyme activities on dusts generated from soils of the southern great plains. American Society of Agronomy Abstracts. 2003 CDROM.
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Progress 10/01/02 to 09/30/03
Outputs
1. What major problem or issue is being resolved and how are you resolving it? The overall goal of this project is to study the basic physical processes that govern wind erosion and dust emissions in agricultural regions at multiple scales, to provide a basis for the development of mitigation strategies. The specific objectives of this project are to: 1) relate sand transport (saltation) and atmospheric turbulence, as affected by soil surface conditions, with dust emissions at the sub-field and field- scale. 2) define plant and soil surface properties that impact wind erosion processes at the field-scale. 3) use long-term dust records and geographic information systems to relate ambient dust levels and potential wind erosion to changing land-use practices at a regional-scale, and to define linkages between climatic conditions and regional dust levels. 2. How serious is the problem? Why does it matter? Wind erosion causes about 44% of the 2.13 billion tons per year of
soil loss from U.S. cropland. In the Great Plains alone, about 5 million acres are moderately to severely damaged by wind erosion each year. Sustainable agriculture is possible only if we conserve soil resources for future generations. Reducing wind erosion helps conserve topsoil and reduces air and water pollution from airborne sediments. Reducing wind erosion can impact agricultural production by reducing production costs. Deposition of transported dust on crops decreases their yield, reduces their economic value, and hinders their processing. Considerable crop losses occur each year from sandblasting of seedlings caused by abrasive damage to plant tissues. The need for a solid scientific approach to the wind erosion problem increases as the world population grows and the need to utilize our resources to the fullest becomes more critical. In addition, objective information regarding the wind erosion process will improve the scientific basis for making decisions on farm
policies and environmental issues. 3. How does it relate to the National Program(s) and National Program Component(s) to which it has been assigned? This CRIS contributes to two components of the ARS NP 203 National Air Quality Program and four components of the Soil Resources Management Programs. Objectives 1 and 3 of this CRIS contribute to the Particulate Emissions from Wind Erosion objective of the Particulate Emissions Component of the Air Quality National Program by developing the science basis for particle emission and control strategies needed for policy and regulatory decisions. This CRIS is also closely tied to the Agricultural Operations objective of the Particulate Emissions Component of the Air Quality National Program by providing information on soil surface conditions impacting particle emissions. Objectives 2 and 3 of this CRIS are closely tied to the Erosion: Wind, Rainfall, Irrigation and Tillage Problems objective of the Soil Conservation and Restoration component
of the ARS NP 202 Soil Resource Management National Program by providing knowledge on plant and surface properties that cause wind erosion that reduces productivity and identifying management practices that cause soil degradation. This CRIS also relates to the Infiltration and Retention and Soil Water Availability objectives of the Soil Water component of the Soil Resource Management Program by providing information on soil properties that impact infiltration as well as wind erosion; the Interactions Between Soil Management and Soil Biota objective of the Soil Biology component of the Soil Resource Management Program by providing information on soil microbiological factors that impact soil properties related to sustainable management; and the Developing Sustainable Soil Management Systems objective of the Sustainable Soil Management Systems component of the Soil Resource Management Program by identifying land use practices that reduce erosion and produce sustainable land management
systems 4. What were the most significant accomplishments this past year? A. Single Most Significant Accomplishment in FY2003: An easy and reliable method to predict the amount of dustiness is needed because once detached from the surface fine dust particles are blown vast distances downwind resulting in significant topsoil loss while negatively impacting air quality. The Wind Erosion and Water Conservation research unit of the Cropping Systems Research Laboratory, Lubbock, TX, reformulated a previously derived equation that relates saltation activity and relative wind strength such that threshold may be calculated from measurements of saltation activity, wind speed, and turbulence intensity and field tests were performed to determine its usefulness on a sandy surface in West Texas. A new method was developed that allows for the rapid determination of the wind speed that dust will begin moving under natural wind conditions, during periods of active sand movement in the field using
commercially available equipment. This new method allows for routine monitoring of surface threshold conditions in the field and will be important in the validation of dust emission models that predict effects of wind erosion on air quality. B. Other Significant Accomplishments: Validation of wind erosion models using field data is needed to understand how reliably and accurately they predict wind erosion. Scientists at the Wind Erosion and Water Conservation Research Unit of the Cropping Systems Research Laboratory, Lubbock, TX, used up to 41 measured wind erosion events to evaluate several wind erosion models currently in use. Although the results were variable, in general, the three erosion models tested (WEQ, WESS, RWEQ) tended to predict less erosion than that observed. These studies could have a significant impact on erosion policy when based on model estimates, since they show that estimates of erosion using models will generally be conservative. C. Significant
Accomplishment/Activities that support special target population: None 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. Developed new unattended sequential dust sampling system to measure dust remotely for weekly periods. This system will provide higher quality atmospheric dust data than now possible with currently available commercial instruments. 6. What do you expect to accomplish, year by year, over the next 3 years? FY2004 Objective 2, Hypothesis 1: We will report residue and crop effectiveness at controlling saltation. Objective 3, Hypothesis 4: Will describe improvements in PM10 aerodynamic diameter measurements using a Vertical Settling Analysis Tubes (VSAT). FY2005 Objective 2, Hypothesis 2: Will release findings on relation of wind erosion roughness parameters and aerodynamic roughness. Objective 2, Hypothesis 3: Will release information on effect of soil management, soil properties and climate on aggregate
stability. Objective 3, Hypothesis 4: We will quantify chemical properties, enzyme activities and the levels and types of microorganisms, including pathogens, transported in dust. FY2006 Objective 1: Will describe refinements in a technique to determine threshold wind speed based on saltation activity and relate dust emission to saltation activity. Objective 3, Hypothesis 4: We will release information that quantifies chemical properties, enzyme activities and the levels and types of microorganisms, including pathogens, transported in dust and publish results. 7. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? A new and potentially useful field instrument was developed in a cooperative effort between the USDA-Agricultural Research Service and Texas
Tech University. The instrument is best described as a flat-plate wind erosion sensor that detects grains as they skip across the face of a piezoelectric sensor. The main constraint to the adoption of this technology is that most researchers in the field of wind erosion research lack the skills necessary to build such a complex electronic device. Hopefully, a private company can be found to manufacture and sell these instruments to a very limited market.
Impacts
(N/A)
Publications
- Van Pelt, R.S., Chavez, J.A., Ketterer, M.E., Arimoto, R., Zobeck, T.M., Gill, T.E. Sediment deposition in an attic near a region of dust provenance: Implication for historic regional dust, radionuclide, and trace element dispersion and dry deposition patterns. Proceeding of the 7th International Conference on the Biogeochemistry of Trace Elements. 2003. CD session SP14. Paper No. 13. p. 2.
- Stout, J.E. Intermittent wind erosion activity in burned semi-arid grassland (abs). Lee, J.A., Zobeck, T.M. editors. 99th Annual Meeting of the Associaton of American Geographers. Available from: http://convention. allacademic.com/aag2003/view_paper_info.html?pub_id=1979part_id1=21388 [2003].
- Stout, J.E. The yellow lake experiment. Lee, J.A., Zobeck, T.M. editors. Proceedings of ICAR5/GCTE-SEN Joint Conference, International Center for Arid and Semi-Arid Lands Studies, Texas Tech University, Lubbock, Texas. 2002. p. 191-194.
- Van Pelt, R.S., Zobeck, T.M., Potter, K.N., Stout, J.E., Popham, T.W. Validation of the wind erosion stochastic simulator (WESS) and the Revised Wind Erosion Equation (RWEQ) for single events. Lee, J.A., Zobeck, T.M. editors. Proceedings of the ICAR5/GGCTE-SEN Joint Conference. International Center for Arid and Semi-Arid Land Studies. Texas Tech University, Lubbock, Texas. 2002. p. 292-295.
- Lee, J.A., Zobeck, T.M. Proceedings of the ICAR5/GCTE-SEN Joint Conference. International Center of Arid and Semi-Arid Land Studies. Texas Tech University, Lubbock, Texas. 2002. 462 p.
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Progress 10/01/01 to 09/30/02
Outputs
1. What major problem or issue is being resolved and how are you resolving it? The overall goal of this project is to study the basic physical processes that govern wind erosion and dust emissions in agricultural regions at multiple scales, to provide a basis for the development of mitigation strategies. The specific objectives of this project are to: 1) relate sand transport (saltation) and atmospheric turbulence, as affected by soil surface conditions, with dust emissions at the sub-field and field scale; 2) define plant and soil-surface properties that impact wind erosion processes at the field scale; and 3) use long-term dust records and geographic information systems to relate ambient dust levels and potential wind erosion to changing land-use practices at a regional scale and define linkages between climatic conditions and regional dust levels. 2. How serious is the problem? Why does it matter? Wind erosion causes about 44% of the 2.13 billion tons per year of
soil loss from U.S. cropland. In the Great Plains alone, about 5 million acres are moderately to severely damaged by wind erosion each year. Sustainable agriculture is possible only if we conserve soil resources for future generations. Reducing wind erosion helps conserve topsoil and reduces air and water pollution from airborne sediments. Reducing wind erosion can impact agricultural production by reducing production costs. Deposition of transported dust on crops decreases their yield, reduces their economic value, and hinders their processing. Considerable crop losses occur each year from "sandblasting" of seedlings caused by abrasive damage to plant tissues. The need for a solid scientific approach to the wind erosion problem increases as the world population grows and the need to utilize our resources to the fullest becomes more critical. In addition, objective information regarding the wind erosion process will improve the scientific basis for making decisions on farm
policies and environmental issues. 3. How does it relate to the national Program(s) and National Program Component(s) to which it has been assigned? This CRIS contributes to two components of the ARS NP 203 National Air Quality Program and four components of the Soil Resources Management Programs (NP202). Objectives 1 and 3 of this CRIS contribute to the Particulate Emissions from Wind Erosion objective of the Particulate Emissions Component of the Air Quality National Program by developing the science basis for particle emission and control strategies needed for policy and regulatory decisions. This CRIS is also closely tied to the Agricultural Operations objective of the Particulate Emissions Component of the Air Quality National Program by providing information on soil surface conditions impacting particle emissions. Objectives 2 and 3 of this CRIS are closely tied to the Erosion: Wind, Rainfall, Irrigation and Tillage Problems objective of the Soil Conservation and Restoration
component of the ARS NP 202 Soil Resource Management National Program by providing knowledge on plant and surface properties that cause wind erosion that reduces productivity and identifying management practices that cause soil degradation. This CRIS also relates to the Infiltration and Retention and Soil Water Availability objectives of the Soil Water component of the Soil Resource Management Program by providing information on soil properties that impact infiltration as well as wind erosion; the Interactions Between Soil Management and Soil Biota objective of the Soil Biology component of the Soil Resource Management Program by providing information on soil microbiological factors that impact soil properties related to sustainable management; and the Developing Sustainable Soil Management Systems objective of the Sustainable Soil Management Systems component of the Soil Resource Management Program by identifying land use practices that reduce erosion and produce sustainable land
management systems. 4. What was your most significant accomplishment this past year? A. Single Most Significant Accomplishment during FY2002: Dust emissions from saline playas are among the largest natural dust sources on the Southern High Plains but little is known why and when dust is emitted. Data on dust emission coupled with climatic data from a large playa lake has been analyzed by scientists with the Wind Erosion and Water Conservation Research Unit of the Cropping Systems Research Laboratory, Lubbock, TX. The results show that playa dust emissions peak during winter when dry conditions prevail and the playa surface is stable during spring when rainfall is more plentiful. It appears that natural dust emissions from Yellow Lake are out of phase with the normal spring- dominated dust emissions from cropland. B. Other Significant Accomplishments: Existing ambient dust measurements have been proposed as an indirect measure of regional wind erosion activity but this has never
been demonstrated. Scientists with the Wind Erosion and Water Conservation Research Unit of the Cropping Systems Research Laboratory, Lubbock, TX, investigated evidence of changing wind erosion activity on the Southern High Plains by using both state and federal regulatory agencies collected dust samples from 1961 to the end of 1982, and more recently ARS scientists collected dust samples from 1998 through 2002. Results indicate that although cropland acres and climate did not change appreciably over the past four decades, wind erosion activity declined by over 70% on the Southern High Plains. This project demonstrated the value of monitoring ambient dust levels to gather information about regional wind erosion activity to provide important information on the reduction in ambient dust levels attributed to modern farming practices. C. Significant Accomplishments/Activities that Support Special Target Populations: None. 5. Describe your major accomplishments over the life of the
project, including their predicted or actual impact? Developed new unattended sequential dust sampling system to measure dust remotely for weekly periods. This system will provide higher quality atmospheric dust data than now possible with currently available commercial instruments. CRADA partners are being sought. 6. What do you expect to accomplish, year by year, over the next 3 years? FY2003: Objective 2, Hypothesis 2: Will describe the relationship of wind erosion roughness parameters and aerodynamic roughness. Objective 3, Hypothesis 1: Will release information on use of atmospheric dust measurements to provide information on regional-scale wind erosion activity. Objective 3, Hypothesis 4: Will describe improvements in PM10 aerodynamic diameter measurements using a Vertical Settling Analysis Tubes (VSAT). FY2004: Objective 1: Will describe a new technique to determine direction of sand transport based on field-scale data. Objective 3, Hypothesis 4: We will quantify chemical
properties, enzyme activities and the levels and types of microorganisms, including pathogens, transported in dust. Will release information on chemical characteristics of dust related to source area. FY2005: Objective 1: Will describe refinements in a technique to determine threshold wind speed based on saltation activity. 7. What technologies have been transferred and to whom? When is the technology likely to become available to the end user (industry, farmer other scientist)? What are the constraints, if known, to the adoption durability of the technology? A new and potentially useful field instrument was developed in a cooperative effort between the USDA-Agricultural Research Service and Texas Tech University. The instrument is best described as a flat-plate wind erosion sensor that detects grains as they skip across the face of a piezoelectric sensor. Within the next year, the design of the new instrument will be made available to field researchers. The main constraint to the
adoption of this technology is that most researchers in the field of wind erosion research lack the skills necessary to build such a complex electronic device. Hopefully, a private company can be found to manufacture and sell these instruments to a very limited market
Impacts
(N/A)
Publications
- Singer, A., Zobeck, T., Poberezsky, L., Argaman, E. The PM10 and PM2.5 dust generation potential of soils/sediments in the southern Aral Sea Basin, Uzbekistan. Proceedings of the Fifth International Conference on Aeolian Research. 2002. p. 343-346.
- Stout, J.E. The Yellow Lake experiment. Proceedings of the Fifth International Conference on Aeolian Research. 2002. p. 191-194.
- Van Pelt, R.S., Zobeck, T.M., Gill, T.E. Sediment deposition in an attic near a region of dust provenance: Implications for historic regional dust dispersion and deposition patters. Proceedings of the Fifth International Conference on Aeolian Research. 2002. p. 347-351.
- Zobeck, T.M., Stout, J.E. , Van Pelt, R.S., Funk, R., Rajot, J.L, Sterk, G. Measurement and data analysis methods for field scale wind erosion studies. Proceedings of the Fifth International Conference on Aeolian Research. 2002. p. 204-207.
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